Roll



Jan 6, 1931. F. R. WOODWARD ROLL Filed 1380'.

Patented Jan. 6, 19311 \UNHTED STATES PATENT OFFICE FREDERICK B. WOODWABD, OF NEWTON, MASSACHUSETTS, ASSIGNOR TO STOWE 8c WOODWABD COMPANY, OF NEWTON UPPER. FALLS, MASSACHUSETTS, A CORPORA- TION 01F MASSACHUSETTS BULL awhile my roll is especially useful as a top press roll in paper making machines to prevent the pulp from sticking to the roll, it is r useful for other rolls in paper making machines and elsewhere.

31b, A feature of my invention is the use. of a plurality of pieces of rock or stone for at least a portion ofthe active surface of the roll and under the generic term rock I include, for example, granite, sand, gravel, quartz and emery. The pieces of rock are, for the purpose of gaining economy Without departing from eficiency, held in desired position by a binder and as a binder I prefer to use rubber, which term includes any suitable rubber compound; This construction is very economical because aninexpensive cast iron core may be used.

In the figure of the drawing, which is an elevation of a roll embodying my invention,

the cast iron core 1 carries the roll 2 made of rubber and granite, the latter being indicated at 3 at the acting surface of the roll.

lln makin my roll ll grind the rock to the desired size and, of course, it may be suitably sifted to make sure that the size is correct. When so ground the rock is mixed or compounded with a suitable binder such as rubber which is fully efiective to hold the ground rock in the desired osition, especially at the acting surface ot the roll, but which is cheaper than the rock.

When rubber is used suitable =vulcanizing of the roll to the core 1 will preferably be had. I much prefer to use crystalline rock,-such as granite or sand, because they are held in place very efiectively by even a film of the rubber or rubber compound.

In compounding my roll I prefer to use about five pounds of rubber or rubber compound to about twenty pounds of rock.

Rolls of the character described when used in paper making machines are usually operated with a doctor pressed against them and the doctor has had a glazing action on the surface ef the roll tendin to cause the paper to stick to the roll but the fact is, as proved by my experiments. that no such tendency exists with my use of rock. This lack of adhesion or sticking may be due to porosity of the rock but the fact is that my roll has made a distinct advance in the art not only in the result accomplished but in economy of manufacture. A r

What'l claim is:

1. A roll comprising pieces of rock forming a portion of the active surface of the roll; and a binder of material other than said rock for holding said pieces in the desired position.

2. A roll comprising pieces of crystalline rock forming a portion of the active surface of the roll; and a rubber binder holding said pieces in the desired position.

REISSUED 3. A roll comprising pieces of granite forming a portion of the active surface of the roll; and a rubber binder holding said pieces in the desired position.

42. A roll comprising a core; pieces of rock forming a portion of the active surface of the roll; and a binder connected to the core and holding said pieces in the desired position. i

5. A roll comprising a core; pieces of crystalline rock forming a portion of the active surface of the roll; and a binder connected to the core and holding said, pieces in the desired position.

6. A roll comprising a core; pieces of granite forming a portion of the active surface of the roll; and a binder connected to the core and holding said pieces in the desired position.

7. A top press roll comprising pieces of rock forming a portion of the active surface of the roll; and a rubber binder holding said pieces in the desired position.

8. A roll comprising pieces of rock forming a portion of the active surface of the roll;

and a rubber binder holding said pieces in the desired position, said rock and rubber being in the proportion of about twenty pounds of rock to about five pounds of rubber.

FREDERICK n. WOODWARD. 

